CVE-2025-12559

mediumpriority · track · 0EPSS 0.002 · 12 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.22% (12th) EPSS

CVSS 4.3 · medium

Is it mine?

30 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to sanitize team email addresses to be visible only to Team Admins, which allows any authenticated user to view team email addresses via the GET /api/v4/channels/{channel_id}/common_teams endpoint

cvss

Technical severity, 0–10. One row per scoring source.

4.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.14.3mediumAV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:Nsecondary · FSTEC (BDU) RU

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:Nsecondary · ENISA EU

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:Nsecondary · responsibledisclosure@mattermost.comexploitability 2.8 · impact 1.4

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:Nsecondary · OSV

v3.14mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-200USCWE-200USCWE-200US

affected products (30)

Products and version ranges known to be affected.

Mattermost Mattermost Server <10.11.5all versionscert_bundDE
Mattermost Mattermost Server <10.12.2all versionscert_bundDE
Mattermost Mattermost Server <10.5.13all versionscert_bundDE
Mattermost Mattermost Server <11.0.3all versionscert_bundDE
Mattermost Mattermost Server <11.1.0all versionscert_bundDE
Mattermost Mattermost≤ Server <11.1.0cert_bundDE
Mattermost Mattermost≤ Server <10.11.5cert_bundDE
Mattermost Mattermost≤ Server <10.12.2cert_bundDE
Mattermost Mattermost≤ Server <10.5.13cert_bundDE
Mattermost Mattermost≤ Server <11.0.3cert_bundDE
Mattermost Mattermost≤ 10.12.0 ≤10.12.1enisa_euvdEU
Mattermost Mattermost≤ 11.0.0 ≤11.0.2enisa_euvdEU
Mattermost Mattermost≤ 10.5.0 ≤10.5.12enisa_euvdEU
Mattermost Mattermost≤ 10.11.0 ≤10.11.4enisa_euvdEU
Mattermost Inc Mattermost10.11.0 → 10.11.4fstec_bduRU
Mattermost Inc Mattermost10.12.0 → 10.12.1fstec_bduRU
Mattermost Inc Mattermost10.5.0 → 10.5.12fstec_bduRU
Mattermost Inc Mattermost11.0.0 → 11.0.2fstec_bduRU
mattermost mattermost server10.11.0 → 10.11.5nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server10.12.0 → 10.12.2nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

showing 20 of 30

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2025-2463Mattermost Server: Mehrere SchwachstellenDeutsch2025-11-02csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Mattermost Server ausnutzen, um Informationen offenzulegen und einen nicht näher spezifizierten Angriff durchzuführen.
GHSA-4g87-9x45-cx2hMattermost fails to sanitize team email addresses2025-11-27ghsa · osvUS
Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to sanitize team email addresses to be visible only to Team Admins, which allows any authenticated user to view team email addresses via the GET /api/v4/channels/{channel_id}/common_teams endpoint
GO-2025-4169Mattermost fails to sanitize team email addresses in github.com/mattermost/mattermost-server2025-12-15vendor · osvUS
Mattermost fails to sanitize team email addresses in github.com/mattermost/mattermost-server. NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions. (If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.) The additional affected modules and versions are: github.com/mattermost/mattermost-server from v10.5.0 before v10.5.13, from v10.11.0 before v10.11.5, from v10.12.0 before v10.12.2, from v11.0.0 before v11.0.3.

also known as (6)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund nvd NVD CVE.org MITRE

published 2025-11-27modified 2026-10-19

references (5)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan